Auto merge of #273 - Eijebong:heapsize, r=emilio

Allow heapsize 0.4

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Author: bors-servo

markup5ever/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "markup5ever"
-version = "0.2.0"
+version = "0.2.1"
 authors = [ "The html5ever Project Developers" ]
 license = "MIT / Apache-2.0"
 repository = "https://github.com/servo/html5ever"
@@ -19,7 +19,7 @@ unstable = ["tendril/unstable"]
 string_cache = "0.5"
 phf = "0.7"
 tendril = "0.3"
-heapsize = { version = "0.3", optional = true }
+heapsize = { version = ">= 0.3, < 0.5", optional = true }
 heapsize_derive = { version = "0.1", optional = true }
 
 [build-dependencies]